Automatic stop mechanism



Dec. 28, 1943. H. 1.. HARTMAN ETAL 2,337,815

AUTOMATIC STOP MECHANISMS Filed July 22, 1942 2 Sheets-Sheet 1 II/l/l/IN EN 0R.

' 1 54. Z BY MR; V

Dec. 28, 1943. I H. L. HARTMAN ETAL 2,337,815

AUTOMATIC STOP MECHANISMS Filed July 22, 1942 2 Sheets-Sheet 2 a I fnvEN 0R. 0 y

17.87:: Ami/my Patented Dec. 28, 1943 UNETED ENT QFFICE AUTOMATIC STOPMECHANISM of Ohio Application July 22, 1942, Serial No. 451,935

3 Claims.

This invention relates to phonographs and relates more particularly toautomatic stop mechanisms therefor.

Our invention relates further to the type of phonographs wherein thephonograph turntable carrying the sound records will be automaticallystopped at the conclusion of the play of said records and whereinmanually operable means are provided for re-starting the rotation ofsaid turntable.

An object of our invention is to provide an automatic stop forphonographs of the type described which will be simple in operation,composed of relatively few parts, inexpensive to manufacture andefiicient in use.

A further object of our invention is to provide means for accomplishingthe purposes aforesaid, which means will not only be simple tomanufactors but will be silent or substantially so in use.

Other objects of our invention and the invention itself will become moreapparent by reference to the following description in connection withthe accompanying drawings, in which draw-'- ings:

Fig. l is a top plan view of an embodiment of our invention.

Fig. 2 is a vertical section taken on the line 2-4?- of Fig. 1 andillustrates the stop mechanism in side elevation;

Fig. 3 is a diagrammatic top plan view of a portion of the mechanism onan enlarged scale, illustrating the parts in another position;

Fig. 4 is a view similar to a portion of Fig. 1 but showing the parts instill another operative position.

In the drawings, at is illustrated a base plate, which is adapted to bemounted in a phonograph cabinet and which carries the usual turntablespindle ll and turntable [2, as well as the tone arm spindle l3 and tonearms l4 adapted to be associated therewith. Mounted below the base plateis an electric motor geared to the turntable spindle H and controlled byan electric switch It to rotate the turntable, the throw lever ll of theswitch projecting upwardly through the base-plate l0 and a. support 18mounted thereon.

Our invention relates, as previously stated, to a combined automatic andmanual control mechanism for the operation of the switch It through thethrow lever H which permits the switch to be manually actuated toenergize the electric motor l at the start of a record playing cycle andsaid switch to be locked in such actuated position until the completionof the playing of the record, the switch then being automaticallyreleased to stop the motor. The motor may further be stopped at any timeduring the playing of a record by means oi the manual control.

It will be noted that the throw lever ll of the switch it is, asillustrated, spring-biased toward the non-playing or off position,indicated by dotted lines in Figs. 1 and 3, and by full lines in Fig. 4.To move the switch to record playing or on position, a manually operatedelement in the form of a bell crank; member is provided. This bell crankmember is pivoted at 20 upon the support it and has an outwardlyprojecting long arm 2! extending beyond the outer periphcry of theturntable l2 and a record R placed thereon so as to be readilyaccessible to the operator as a manually operated handle. A relativelyshorter arm 22 of the bell crank member projects into the path of thethrow lever I! to the on position, shown in Figs. 1 and 3.

To look the switch it in the said on recordplaying position, we providea latch member 25, which is pivoted on the support l8 at 26 and formedwith a slight shoulder at 21 adjacent its throw lever engaging end. Thislatch 25 is constantly urged toward the switch, as by a tension spring28 ecured to upstanding ears 29 and 30, on the latch and the supportrespectively. Thus, when the throw lever ll has been moved a sumoientdistance to actuate the switch the shoulder 27 on the latch engages thethrow lever, as illustrated in Figs. 1 and 3, and prevents its return.

To release the latch automatically, at the end of the record playingcycle, we utilize the ovement of the tone arm M as it swings inwardlywhile following the playing groove G of the record. An arm 35 is securedto the tone arm spindle it, thus partaking of the tone arm movements,and carries a depending pin 35 adapted to be adjustably positionedthereon. As the phonograph needle, indicated generally in Fig. 1 at 31,leaves the final convolution of the playing groove, and is movedinwardly by the usual spiral terminal groove, the pin 36 carried by thearm 35 engages an extension 38 of the latch member 25, as indicated inbroken lines in Figs. 1 and 3.

A slight additional movement of the needle is then sufilcient to swingthe latch and withdraw the shoulder 21 from its locked engagement withthe throw lever H. The latter is thus freed and snaps back to its offposition, under the influence of its own spring (not shown). In sodoing, the throw lever ll engages the shorter arm 22 of the bell crankand thus moves the longer arm 2| thereof to its original positionillustrated in Fig. 4 where it remains resting against a stop 39extending upwardly from the support l8.

An additional releasing means is preferably provided which will effectunlatching, in cases where records are not provided with the inwardlyspiralling terminal groove described or where the groove does not extendinwardly a sufiicient distance but is rather provided with an eccentricclosed path, as shown at E in Fig. 1. In

either of these cases the needle reverses its di-' spring 44 extendsbetween upstanding ears 45 and 45, on the arm 43 of the pawl 40 andlatch 25 respectively, and said spring normally retains the arm 43against an upwardly projecting stop 41 on the latch. The arm 35, whichis carried by the tone arm spindle, is further provided with an arcuateend, concentric with the spindle and serrated as at 48.

When the latch 25 is in switch-locking position, the knife edge 42 ofthe pawl projects within the path of travel of the arm 35, as at 42a inFig. 3, and thus the pawl is rocked counterclockwise about its pivot 4|by the arm 35 and engages the teeth 48 as the tone arm reproducingneedle reaches the end of the playing groove G. The pawl 40 is, at thistime, in the full line position of Fig. 3 and the knife edge 42 engagesthe arm 35 and as the arm 35 continues its forward motion, the teeth 48slip past the knife edge 42 one by one. Upon any slight reversal ofdirection, however, the knife edge is moved in a clockwise direction,Fig. 3, to a position such as shown in broken lines at 42b and the pivot4| is forced backwardly to the position llb. This movement of the pivot4| by the arm 35 swings the latch 25 counterclockwise about its pivot 26sufiiciently to release the shoulder 21 from its contact with the throwlever I1, and the switch returns to its oif position.

A third and manual means is preferably provided whereby the motor may bede-energized at any time by the operator. For this purpose, the latchmember 25 is extended beyond the shoulder 21 to provide an oblique face50 which is adapted to be engaged by the end of the bell crank arm 22.It Will be noted in Fig. 1 that clockwise movement of the bell crank, bymeans of the handle 2|, from the position there shown, will cam theoblique face 50 to the right. The latch member 25 will thus be turnedcounterclockwise about its pivot 26 to withdraw the shoulder 21 from thethrow lever I! to release the switch.

- The throw lever ll of the switch may be manually reset andautomatically latched in position at any time after the tone arm hasbeen swung outwardly a sufficient distance to cause the arm 35 to clearthe knife edge 42 and thus to allow the latter again to project withinthepath of the arm's arcuate end. A stop pin is preferably providedwhich, on being engaged by thearm 35, Fig. 4, limits the outward swingof the tone arm. It will also be noted that the turntable spindle llitself comprises an inward stop for the tone arm whereby the arm 35 isprevented from swinging so far as to cause the pin 36 to travel beyondthe extension 38 of the latch 25.

Thus, it can readily be seen that we have provided a simple andeificient switch control for phonographs manually initiated and manuallystopped at any time during a record playing cycle but which, in anyevent, at the termination of a record playing cycle, will beautomatically stopped whether said record be provided with a terminalgroove or not.

We have shown and described herein but a single embodiment of ourautomatic stop mechanism but it will be apparent that numerous changesand departures could be made from the form herein illustrated anddescribed but without departing from the spirit of our invention and thescope of the appended claims.

We claim:

1. In a phonograph, the combination with a tone arm of an electric motorand switch means therefor whereby said motor may be energized tocommunicate movement to a turntable, of manually operable meanscomprising a handle portion and a switch engaging portion, latch meansinterposed between said manually operable means and an arm carried bysaid tone arm, said latch means having a shoulder portion adapted tolock said switch in motor operating position after said switch has beenplaced in such position by said manually operable means, means furthercarried by said latch means adapted to be contacted by said manuallyoperable means to withdraw said shoulder from its locked engagement withsaid switch whereby said switch is restored to its off or non-operatingposition.

2. In a phonograph, the combination of manually operable means pivotallysecured to a support mounted upon a phonograph base, said manual meansbeing provided with a projecting tongue portion, an electric motordisposed beneath said support and having a motor switch associatedtherewith, said motor switch having a throw lever, said throw leverprojecting through said support and adapted to be engaged by said tongueportion of said manual means whereby said throw lever is placed in onposition whereupon said switch is engaged by locking means carried bylatch means pivoted upon said support, an arm carried by said tone armand extending laterally thereof, said laterally extending arm adapted toengage a portion of said latch means whereupon said latch means isrotated in a substantially counter-clockwise direction about its pivot,tne locking means carried by said latch being moved out of contact withsaid throw lever and said throw lever being restored to an off position.

3. In a. phonograph, a turntable, a turntable baseplate, a motorenergizing switch, said switch mounted on the underside of thebaseplate, a throw lever secured to said switch and adapted to actuatesaid switch wherefore the motor may be energized or de-energized asdesired, said throw lever projecting upwardly through said base plate,manually operated control means mounted upon said base plate and adaptedto contact said throw lever to cause said switch to be actuated, latchmeans associated with said throw lever, said manually operated controlmeans comprising a bellcrank member having a pair of arm members, onearm member being relatively longer than said other arm, said longerwhence said latch is swung out of its locked position with said throwlever, the said lever under the influence of spring means associatedtherewith snapping back into its original spring biased ofi positioncarrying with it in its rearward -movement the shorter arm of saidbellcrank whereby the said longer arm of said bellcrank is returned toits original off position.

HERBERT L. HARTMAN. JOSEPH BENDER, JR.

